Data analysis shows that Minneapolis police took 2.1 million records in 90 days.

A Minneapolis-based data scientist has taken the discussion of the potential misuse of license plate reader data to an entirely new level—he claims that he has determined the location of the city’s two stationary license plate readers simply by studying a 90-day data set.

“Within three minutes of sending the e-mail to my contact at the Minneapolis Police Department Records Information Unit, my phone was ringing,” Mark Pitts, who runs a local firm called Datalytics LLC, wrote Sunday on his company’s blog. “And as long as the locations of the cameras remain confidential, I plan to keep them that way.”

He detailed the technique to Ars, and as far as we can tell, it seems quite plausible. The Minneapolis Police Department (MPD) declined to confirm or deny that the department had been in contact with Pitts, and it would not say whether the locations he found are accurate.

As we reported earlier this year, license plate readers are rapidly growingly around the country. High-speed optical character recognition can compare observed plates against a "hot list" of wanted vehicles at 60 plates per second, and these tools are creating millions of records nationwide every single day. Each record includes what plate was spotted, where and when. In some cases, such records are stored indefinitely.

In Minnesota, a rather liberal open records state law known as the Data Practices Act makes all government data public by default, which includes any license plate data. That means (for now) that anyone, from anywhere, can request the entire data set from any law enforcement agency.

Just last week, Minneapolis mayor R.T. Rybak, requested to a state committee that the data be immediately re-classified as “non-public.” So far, Sgt. Palmer of the MPD did tell Ars that they have fulfilled nine requests for a 90-day LPR data set, sent by postal mail on a 4GB flash drive. In this case, the data covers August 30, 2012 through November 29, 2012.

2.1 million records in 90 days

Pitts requested and received the entire 90-day data set in late November. On Sunday, he posted animated videos of behavioral patterns that could be gleaned from the data and found some astonishing information about what an armada of just 10 LPRs can do over a 90-day period.

“In three months with just eight mobile readers and two stationary readers, the MPD collected over 2.1 million license plate reads,” he noted. “Before releasing the data, the MPD deleted the GPS coordinates of data collected by the stationary hidden cameras to protect their locations. Of the 2.1 million reads, almost 1.3 million came from the two stationary cameras.”

The Minneapolis data scientist also suggests that it would be difficult to track any one individual plate over time.

“Of the 2.1 million reads, there are just over 621,000 unique plate numbers in this data,” he wrote.

“The majority of those, 360,000, were read only once. In fact, 530,000 were read four times or less in the three-month period. If we exclude the reads by the stationary cameras, which are not located any place you should worry about being seen or stalked, and we exclude police and other government plates, there are only about 8,000 unique plate numbers that have been tagged ten times or more in the three-month period. To track someone, you would typically need more hits to establish a pattern (unless you really got lucky). Only 75 plates have been hit 40 times or more by a mobile reader. While you could certainly use these data and a little luck to track and find a vehicle, I would estimate the risk to any single individual is very low.”

Are your movements private?

Privacy experts have been impressed by the scope of Pitts’ analysis.

“This study is a good demonstration not only of how much information is collected, but also how much additional information can be extracted through data analysis,” Woodrow Hartzog, a law professor at the Cumberland School of Law at Samford University, told Ars.

He and other privacy experts have consistently expressed concern over the use and potential misuse of such LPR data.

“How is this data being used internally?” Hartzog added. “Does the MPD plan to aggregate, store, and potentially release this data indefinitely? Is there any way for individuals to correct false positives? This study shows the utility of data transparency, which is one of the established fair information practices and allows individuals to verify and challenge data collection by the government.”

Kade Crockford, the director of the Technology for Liberty program at the American Civil Liberties Union (ACLU) of Massachusetts, who has been following LPR deployments in her home state and nationwide for some time now, said that Pitts downplays the individual privacy implications.

“It's true that law enforcement will likely find all sorts of heretofore undiscovered uses for databases chock full of our travel history information, and this kind of long-term location tracking raises significant privacy and Fourth Amendment issues,” she told Ars.

“Ultimately, the only way to prevent abuse against ordinary people or the police is to stop storing non-hit license plate data in the first place. Police should use it immediately (to find stolen cars, for example) or chuck it, and if they do that all of these problems go away—those that threaten the secrecy of police movements and the privacy of ordinary motorists alike.”

Promoted Comments

Hate to be that guy again, after the last drubbing I got, but since nobody ever gave a real answer I've got to ask again: So what?

Please, be specific. What are you worried about the police being able to do, could they do that without this technology, and why would they do what you're worried about?

And I'm in Minneapolis, so my plate may be among those captured.

The problem isn't "what will they do?" The problem is that if they don't have anything to do with it, why keep it?

Fundamentally, it comes down to the question of how much data you are comfortable with a government collecting. If you are fine with the government collecting and storing tracking data, then your questions are the right ones to ask - since there is no evidence of misuse of data, there is no reason to object. However, if you believe that the government should only be collecting this type of data as needed, then your questions are wrong - what they could/would/should/will do is irrelevant and the data should not be stored.

As for me, I don't have any specific objection to actions that they may be able to take. But, I don't see any reason for the government to store my tags for any length of time if they do not register on a list compiled for specific and reasonable law enforcement purposes (such as finding stolen vehicles).

Admittedly, I used some pretty clever geospatial-temporal statistical analysis to do it, so repeating my analysis would be a challenge for most. I gave MPD the information they would need to better redact the data to prevent someone with bad intentions from doing so.

Then he goes on to say that while criminals don't have the 'chops' (his word) to do what he could do, that nefarious entities such as governments and organizations could.

Hell, it looks like there was GPS metadata in the requested file. If there were 10 separate sets of data, and you plot them vs. time, and two of the data sets gps coordinates don't f'ing move while the other 8 do, it's not hard to tell which data sets are coming from vehicles and which ones are stationary and where. It might just be me, but the guy seems pretty full of himself.

Hate to be that guy again, after the last drubbing I got, but since nobody ever gave a real answer I've got to ask again: So what?

Please, be specific. What are you worried about the police being able to do, could they do that without this technology, and why would they do what you're worried about?

And I'm in Minneapolis, so my plate may be among those captured.

The problem isn't "what will they do?" The problem is that if they don't have anything to do with it, why keep it?

Fundamentally, it comes down to the question of how much data you are comfortable with a government collecting. If you are fine with the government collecting and storing tracking data, then your questions are the right ones to ask - since there is no evidence of misuse of data, there is no reason to object. However, if you believe that the government should only be collecting this type of data as needed, then your questions are wrong - what they could/would/should/will do is irrelevant and the data should not be stored.

As for me, I don't have any specific objection to actions that they may be able to take. But, I don't see any reason for the government to store my tags for any length of time if they do not register on a list compiled for specific and reasonable law enforcement purposes (such as finding stolen vehicles).

Admittedly, I used some pretty clever geospatial-temporal statistical analysis to do it, so repeating my analysis would be a challenge for most. I gave MPD the information they would need to better redact the data to prevent someone with bad intentions from doing so.

Then he goes on to say that while criminals don't have the 'chops' (his word) to do what he could do, that nefarious entities such as governments and organizations could.

Hell, it looks like there was GPS metadata in the requested file. If there were 10 separate sets of data, and you plot them vs. time, and two of the data sets gps coordinates don't f'ing move while the other 8 do, it's not hard to tell which data sets are coming from vehicles and which ones are stationary and where. It might just be me, but the guy seems pretty full of himself.

Admittedly, I used some pretty clever geospatial-temporal statistical analysis to do it, so repeating my analysis would be a challenge for most. I gave MPD the information they would need to better redact the data to prevent someone with bad intentions from doing so.

Then he goes on to say that while criminals don't have the 'chops' (his word) to do what he could do, that nefarious entities such as governments and organizations could.

Hell, it looks like there was GPS metadata in the requested file. If there were 10 separate sets of data, and you plot them vs. time, and two of the data sets gps coordinates don't f'ing move while the other 8 do, it's not hard to tell which data sets are coming from vehicles and which ones are stationary and where. It might just be me, but the guy seems pretty full of himself.

Yep. I noticed that.

Besides computer criminals are far more clever than he thinks. More clever than him, or security officers at most corporations, or authorities. And they do their dirty deeds from coffee shops in places like St. Petersburg or Minsk or Beijing, far out of reach of their victims.

I could keep posting stuff like this. That in mind, I'm disinclined to allow the police to collect much of anything without some damn good explanation as to how they will use it to public benefit. And something to hold them to that too.

“Ultimately, the only way to prevent abuse against ordinary people or the police is to stop storing non-hit license plate data in the first place. Police should use it immediately (to find stolen cars, for example) or chuck it, and if they do that all of these problems go away—those that threaten the secrecy of police movements and the privacy of ordinary motorists alike.”

Hate to be that guy again, after the last drubbing I got, but since nobody ever gave a real answer I've got to ask again: So what?

Please, be specific. What are you worried about the police being able to do, could they do that without this technology, and why would they do what you're worried about?

And I'm in Minneapolis, so my plate may be among those captured.

"So what?" This sounds a lot like the "If you aren't doing anything wrong, you have nothing to worry about" argument that I hear from people who are apologists for governmental privacy violations. So what if the government tracks your movements? So what if the government puts a GPS tracking device on your car without a warrant? So what?

Or you happen to maybe not agree with said government, and they happen to decide you're a "threat".

Again, I'm not looking for the abstract. I want to know what the objection is. I understand the paranoid fantasy that people will somehow be crushed under the dictatorial powers of an abusive police department. Whatever. What I don't get is how knowing that my car at some point passed one of two fixed points in the city helps that dictator crush my spirit or whatever.

“Ultimately, the only way to prevent abuse against ordinary people or the police is to stop storing non-hit license plate data in the first place. Police should use it immediately (to find stolen cars, for example) or chuck it, and if they do that all of these problems go away—those that threaten the secrecy of police movements and the privacy of ordinary motorists alike.”

How about finding an abducted child?

the "think of the children" argument.

if they knew exactly what car it was and when they have probably solved the case already.

Hate to be that guy again, after the last drubbing I got, but since nobody ever gave a real answer I've got to ask again: So what?

Please, be specific. What are you worried about the police being able to do, could they do that without this technology, and why would they do what you're worried about?

And I'm in Minneapolis, so my plate may be among those captured.

I'm worried about the police using the data to make their job easier. And by easier I mean quickly closing cases with circumstantial evidence, and convicting the wrong people. We do not want to see it this way but your average cop is like anyone else. They want their working day to pass as easily as possible with as few hassles as possible. The problem here is that while there are not many short term problems when a doctor writes you a scrip for prozac to help your cold; when cops get lazy humans get fucked. It could be stamping "Gang related" on murders that have no good clues, it could be grabbing license data and just convicting someone to get a case off the books.

Now most people feel safer if they carry a "it will never happen to me/you!" belief, the problem is that it does happen to people. This is a comfortable but stupid way to live. In my teen years I had many cops use torture among other things to try to get me to confess to something I didn't do just to get a case off the books. Just using some illegal search and seizure data is less morally objectionable that torturing kids, and so it is easier to do. If they will torture kids already...Unless it is OK to do surveillance on every person in the state, getting a computer to watch the people for you is not right. "Just collecting data" doesn't fly here any more than tapping all the phones in the state, just to collect data.

Admittedly, I used some pretty clever geospatial-temporal statistical analysis to do it, so repeating my analysis would be a challenge for most. I gave MPD the information they would need to better redact the data to prevent someone with bad intentions from doing so.

Then he goes on to say that while criminals don't have the 'chops' (his word) to do what he could do, that nefarious entities such as governments and organizations could.

Hell, it looks like there was GPS metadata in the requested file. If there were 10 separate sets of data, and you plot them vs. time, and two of the data sets gps coordinates don't f'ing move while the other 8 do, it's not hard to tell which data sets are coming from vehicles and which ones are stationary and where. It might just be me, but the guy seems pretty full of himself.

I think that was covered here:

Quote:

“In three months with just eight mobile readers and two stationary readers, the MPD collected over 2.1 million license plate reads,” he noted. “Before releasing the data, the MPD deleted the GPS coordinates of data collected by the stationary hidden cameras to protect their locations. Of the 2.1 million reads, almost 1.3 million came from the two stationary cameras.”.

“Ultimately, the only way to prevent abuse against ordinary people or the police is to stop storing non-hit license plate data in the first place. Police should use it immediately (to find stolen cars, for example) or chuck it, and if they do that all of these problems go away—those that threaten the secrecy of police movements and the privacy of ordinary motorists alike.”

How about finding an abducted child?

the "think of the children" argument.

if they knew exactly what car it was and when they have probably solved the case already.

Have you never heard of Amber Alerts? In California we have giant LCD billboards all over the freeways, and every few months they tell us that a child was abducted in a "red Toyota Camry, license plate 6ABC789" and ask us to call 911 if we see said car.

Clearly it's all just a ruse, because once the government has that much info, the case is solved, right?

It took me a while to figure out what this article was actually about.

First I thought we found something secret, then I thought we were being tracked somehow, then I thought privacy concerns, now it seems it's just an interesting case of government data negligence.

Let's consider the boring truth, once again, of how government systems typically get made (read: lowest bidder consulting with hard deadlines).

I've worked on government contracts where last minute requirements often come from people who are hardly familiar with the nature of the project. Coming down to the wire, a loud voice mandates to "keep all the data... just in case." It's the cover-your-ass, no-extra-work approach. The project gets wrapped up and deployed... people move on with their lives.

Years later we have data negligence where people figure out how to play with large data sets and extrapolate meaning. Where's the solution?

"So what?" This sounds a lot like the "If you aren't doing anything wrong, you have nothing to worry about" argument that I hear from people who are apologists for governmental privacy violations. So what if the government tracks your movements? So what if the government puts a GPS tracking device on your car without a warrant? So what?

This has nothing to do with the "if you're not doing anything wrong" argument. I find those as tired as you do. This is different. First, you're assuming a privacy violation. Is your car's location on a public road private information? Second, the concern about tracking your movements isn't mutually exclusive with existing methods, and therefore isn't an argument against collecting this data.

Putting a tracking device on your person or vehicle? That to me seems like a leap beyond what's possible with just simple observation. I can see requiring a warrant for something like that. But maybe there's no distinction there. I'm persuadable.

“Ultimately, the only way to prevent abuse against ordinary people or the police is to stop storing non-hit license plate data in the first place. Police should use it immediately (to find stolen cars, for example) or chuck it, and if they do that all of these problems go away—those that threaten the secrecy of police movements and the privacy of ordinary motorists alike.”

How about finding an abducted child?

the "think of the children" argument.

if they knew exactly what car it was and when they have probably solved the case already.

Have you never heard of Amber Alerts? In California we have giant LCD billboards all over the freeways, and every few months they tell us that a child was abducted in a "red Toyota Camry, license plate 6ABC789" and ask us to call 911 if we see said car.

Clearly it's all just a ruse, because once the government has that much info, the case is solved, right?

This is just another case where they can use it immediately, like finding a stolen car. Are they really going to pour through years of license plate data (terabytes of it) to try and guess where that car usually goes? No, that data is sketchy anyway which is the point of the article, and it's probably not even more useful than the data that they already have about the person who registered the plate. Instead they're going to look and see where that car goes next based on new hits by license plate readers, because those new hits are much more useful and timely

“Ultimately, the only way to prevent abuse against ordinary people or the police is to stop storing non-hit license plate data in the first place. Police should use it immediately (to find stolen cars, for example) or chuck it, and if they do that all of these problems go away—those that threaten the secrecy of police movements and the privacy of ordinary motorists alike.”

How about finding an abducted child?

the "think of the children" argument.

if they knew exactly what car it was and when they have probably solved the case already.

Not quite. What vehicle, when, and were. Makes it easier to focus ones efforts.

Or you happen to maybe not agree with said government, and they happen to decide you're a "threat".

Again, I'm not looking for the abstract. I want to know what the objection is. I understand the paranoid fantasy that people will somehow be crushed under the dictatorial powers of an abusive police department. Whatever. What I don't get is how knowing that my car at some point passed one of two fixed points in the city helps that dictator crush my spirit or whatever.

That's no more abstract than your presumption that there will only ever be two fixed points collecting data, or that it won't be abused when all the evidence of history shows how power corrupts and how government becomes more oppressive the more powerful it becomes and the less free/private the citizens' lives are.

"So what?" This sounds a lot like the "If you aren't doing anything wrong, you have nothing to worry about" argument that I hear from people who are apologists for governmental privacy violations. So what if the government tracks your movements? So what if the government puts a GPS tracking device on your car without a warrant? So what?

This has nothing to do with the "if you're not doing anything wrong" argument. I find those as tired as you do. This is different. First, you're assuming a privacy violation. Is your car's location on a public road private information? Second, the concern about tracking your movements isn't mutually exclusive with existing methods, and therefore isn't an argument against collecting this data.

Putting a tracking device on your person or vehicle? That to me seems like a leap beyond what's possible with just simple observation. I can see requiring a warrant for something like that. But maybe there's no distinction there. I'm persuadable.

Courts have already ruled against unwarranted GPS trackers on cars on public roads, and those were used on specific cars of known suspects. Buy enough license plate readers and keep the data long enough and not only are you making an end-run around the same issue that GPS has, but you're also tracking the movements of tons of people who you don't know are suspects.

Incidentally they're already trying to do an end-run around GPS limitations with cellphone tracking data, but at least that is (so far) done on a targeted basis and not just "give me cellphone tracking data on everybody, I'll decide which is important later." It's not always enough to say "they won't abuse it", you have to make sure they can't abuse it if there's no greater reason to have it

This is also why people don't like the idea of computers doing a dragnet of email meta-information for everybody in America. It's not narrowly focusing on people even vaguely suspected to be causing a problem. It's also why they fire and/or arrest people who work for the police and abuse the registration databases even for non-malicious curiosity's sake

Admittedly, I used some pretty clever geospatial-temporal statistical analysis to do it, so repeating my analysis would be a challenge for most. I gave MPD the information they would need to better redact the data to prevent someone with bad intentions from doing so.

Then he goes on to say that while criminals don't have the 'chops' (his word) to do what he could do, that nefarious entities such as governments and organizations could.

Hell, it looks like there was GPS metadata in the requested file. If there were 10 separate sets of data, and you plot them vs. time, and two of the data sets gps coordinates don't f'ing move while the other 8 do, it's not hard to tell which data sets are coming from vehicles and which ones are stationary and where. It might just be me, but the guy seems pretty full of himself.

I think that was covered here:

Quote:

“In three months with just eight mobile readers and two stationary readers, the MPD collected over 2.1 million license plate reads,” he noted. “Before releasing the data, the MPD deleted the GPS coordinates of data collected by the stationary hidden cameras to protect their locations. Of the 2.1 million reads, almost 1.3 million came from the two stationary cameras.”.

Yes, the dataset didn't have stationary GPS coordinates, so someone would have to do some work to figure out where the stationary cams were. However, it still doesn't seem like it would be too hard: look for plates which are scanned by more than one scanner in a short period of time. As you find more of these, you increase the probability of having located a stationary scanner: each time the mobile units drive past the stationary camera's location, the duplicate hits are going to reveal its location. It isn't very difficult.

Later on in his blog post, the researcher proposes some uses of this data in a centralized environment.

Quote:

Perhaps someday these data could be used to do things like find a kidnapped child during an Amber Alert. Imagine combining and storing data from all agencies into a centralized, secure repository (with the proper oversight, of course). The historical patterns could be used, for example, to determine in real-time likely routes the suspect would take, and thus give police a better chance of finding the child quickly.

I'm not sure I buy it. I dont see how the plate scanners could reveal any habits which are different than your standard traffic density graphs (showing which routes are best in a particular type of rush-hour traffic).

That's no more abstract than your presumption that there will only ever be two fixed points collecting data, or that it won't be abused when all the evidence of history shows how power corrupts and how government becomes more oppressive the more powerful it becomes and the less free/private the citizens' lives are.

That's no more abstract than your presumption that there will only ever be two fixed points collecting data, or that it won't be abused when all the evidence of history shows how power corrupts and how government becomes more oppressive the more powerful it becomes and the less free/private the citizens' lives are.

Abused... how?

You don't even have to assume a grand conspiracy here. People already have abused the police license registration databases to:

The issue is not 2 LPR points; the issue is that in the future, with cheap cameras, terabyte disks, GPS and the internet - every police car will become a data collector, as will any major intersection in the city. Or the country.

Then, your movements any time will become a datamine for the police.Forget where you went last Thursday, and tell the police the wrong thing? (I know I can confuse Thursday and Wednesday night a week later) Now yo are guilty of obstruction of justice, because the computer never lies.

Some bozo prints out your licnse plate and goes on a drive rampage? Sucks to be you. (I heard of someone taking a photo of the teacher's license plate, printing it out on an inkjet, and taping it over their plate. Then they run a few red lights where there are red light cams. Those cameras never lie... Better hope you have a unique car.)

There's always substituting brute force for police work. the first datamining I read about was when the police were seeking Son of Sam. They crosslisted every male of a certain age and height range, and ownership records of gold or brown Volkswagens within X miles of New York City. Then they went looking for them all, to question them. Guess what? The witnesses were mistaken, SoS did not drive a Volkswagen.

It's analogous to - you get arrested for X, now they have complete records to make you look bad. In th paranoid dictatorship, they can say where you went (you drove into the neighbourhood where this registered sex offender lives, were you visting him?) what you posted on every chat board (you said the government was out to get you, are you mentaly unhinged? Maybe that's why you could have done this crime?) every phone number you dialed (of course he did not call X from his cell, but he was at the mall according to car plate data when someone called from a payphone at the restaurant 5 blocks away from the mall)

Will it get to the point where "these 10 cars drove by the highway LPR, can we get search warrants to see if any of them have the stolen goods at home?"

Even if you are innocent, who wants to be "guilty as OJ", basically, found innocent but completely broke by the lawyer bills.

If a corrupt official wants dirt on me, he can get someone to follow me around. Alternatively, I guess, he can look through millions of data points to see if I passed by some fixed point in the city. Horrors!

The difference is that that's *hard*; it at least requires effort. If legit officials want to do the same thing, they need a judge to sign off on it. That right there is what I want. I'm fine with occasional, justified, overseen departures from privacy, but if it's free and easy, oversight becomes difficult/impossible.

These words feel incredibly stale as I type them, but the rules need to change with the technology. If law enforcement wants to track someone, they need to justify it, and we need to be able to hold them accountable for it.

On of your friends from high school is a chronic break-in artist. according to plate data, he drops by within a week of every break-in. they'd never think it's because you play video games or D&D or something. Or he's a drug dealer, maybe you're his supplier. You must either (a) be involved or (b) helping him sell the goods, based on his driving pattern. Cops kick in your door with a search warrant.

My issue with license plate readers is all about data retention and what a large collection of data allows for.

Are the rights of drivers violated when a cop with readers mounted is sitting on the side of a major highway ramp reading the plate of every car that passes? No.

What about if there is a reader at every street corner? No.

What about if all that data is collected and stored to the point that I could easily plot the path of any given car on any given date and time without any warrant? Yes - I certainly think so.

Creepier yet, it's not hard to use the gathered data to plot predicted travel, or find outliers.

For example, let's say there was a murder, so I pull up all outliers for that area - cars that are not normally there. A car comes up as a possible interest. I call the owner asking him why he was in the area - he dinies he was ever there. I have him in a lie, he's now a suspect. Except the only reason he was there is that he missed his normal exist and had to take a backstreet home and forgot all about it.

The problem with this kind of data is that while it can be a phonomenal tool for tracking, finding and catching criminals, it's an awfuly large net to cast and it's bound to catch some innocent people.

I like the idea of plate readers being used against a "black list" of known suspect cars - I loathe the idea of plate readers recording and logging all plates.

I think the importance of these data aren't just in these records, but in how they can be combined with other data sets. Knowing where I was at 4 different times in a day, for example, might not be too exciting but if you combine that with IP logs, transaction records, phone records and more these data might be enough to build a more accurate picture of me.

Each data point might not erode a lot of my privacy, but it does erode it. The more data, the more erosion.

What are you worried about the police being able to do, could they do that without this technology, and why would they do what you're worried about?

I'm worried that the police will be able to build a picture of my day-to-day activities. They could do that without this specific technology, but this is part of a class of technologies that enables this activity. They do it because they want to know what everyone is doing, ostensibly for fighting crime.

Note that I am worried about this despite the fact that I do not commit crime. That's the part I think you're not understanding.

The issue is not 2 LPR points; the issue is that in the future, with cheap cameras, terabyte disks, GPS and the internet - every police car will become a data collector, as will any major intersection in the city. Or the country.

Two is enough though really. Two LPRs that are close together is all you need to run a blackmail business for people who moved too fast between them to not be speeding. Almost everybody speeds, and that's the perfect situation for someone who wants to arrest you for "just anything" as harassment

We've given reasons why this could be abused even with only a few LPRs and a comprehensive database, and the entire article was basically a statement of "keeping this data isn't even useful for legitimate police work unless there are a lot more readers." It's not useful if there aren't a lot of readers, but it gets downright scary if there are.

My favorite suggestion once was that a couple in a divorce / custody battle could subpoena the data to help track a spouse and bolster their case. He goes to the bar area of town a lot. he's never home until 5:30PM, can't be relied on. She's headed to that abusive boyfriend's neighbourhood. etc. He was 15 minute late picking up Junior at school 4 times in the last month.

Or it's a wrongful dismissal suit, and the company will subpoena the records to show you arrived at work at 9:03 not 9:00AM.

The government has the data, it's relevant to the case, what right do they have to withhold it?

I think the importance of these data aren't just in these records, but in how they can be combined with other data sets. Knowing where I was at 4 different times in a day, for example, might not be too exciting but if you combine that with IP logs, transaction records, phone records and more these data might be enough to build a more accurate picture of me.

Each data point might not erode a lot of my privacy, but it does erode it. The more data, the more erosion.

Or the picture (no pun intended) one gets from you using your debit/credit card.

I'm not American but don't see what the big deal is. If my car was stolen and recovered quickly with little damage or before a crime was commited with it, how is that a bad thing?

I don't think they're using it to watch a normal person grab a small bad of weed, but heavy hitters, terrorists etc. Also because America is turning into the wild wild west imagine how it could help with these shootings etc. They'd be able to see dude went to and from the shooting range then to the gun store or if there were any accomplices which need to be arrested. People need to stop being paranoid, your browser stores more info then they're plate cams!

Even back in the 1980's, Reagan's government proposed a new "classified" category - individual pieces of data were not private, or even hidden, but a collected database would be considered national security classified. I.e. the fact that company A buys something is not classified, but if they are doing defense work, the complete database of what they purchase from all suppliers, or their trucking records, etc. could be. Where someone works may not be classified, but a complete list of government employees is.

This anticipated privacy data but for paranoid purposes. It's the "technology changes everything" argument. If I have to find and search every phone book in the northeast, it's a heckuva lot harder to stalk someone than if I simply google. The police will stalk a lot less people if it takes a team of people to do it, than if they can simply plunk a GPS tracker on your car and do a download (automatically) every night by cellular network.

As for the Amber Alert scenario, the data could be deleted within a day, or a week... by then it's likely too late. Besides, if all it takes to fool the system is paper plates, then expect that to become the norm.

Another side effect - when speed cameras were legailized in Ontario 2 decades ago, the first thing that happened - police traffic patrols disappeared. Why look for speeders when a camera was doing that? So as long as nobody was parked on the side of the road, pretty obvious on a freeway, go as fast as you want. Nobody unmarked cars looking for bad driving - cutting people off, bad lane changes, etc.

The easier it is to collect data, the more specific the reason should be for collecting and especially storing it.

I'm not American but don't see what the big deal is. If my car was stolen and recovered quickly with little damage or before a crime was commited with it, how is that a bad thing?

I don't think they're using it to watch a normal person grab a small bad of weed, but heavy hitters, terrorists etc. Also because America is turning into the wild wild west imagine how it could help with these shootings etc. They'd be able to see dude went to and from the shooting range then to the gun store or if there were any accomplices which need to be arrested. People need to stop being paranoid, your browser stores more info then they're plate cams!

Unfortunately, in most of these cases, this data is irrelevant. By the time they check this, the trouble is over, and there are no accomplices or miscreant gunshops to blame, it was all perfectly legal.

Hate to be that guy again, after the last drubbing I got, but since nobody ever gave a real answer I've got to ask again: So what?

Please, be specific. What are you worried about the police being able to do, could they do that without this technology, and why would they do what you're worried about?

And I'm in Minneapolis, so my plate may be among those captured.

My concern is other uses for which the data could be used. For example your wife obtains a copy of the data and uses it in a court proceeding against you. Your employer searches it and discovers you were at an oncologists office and the next thing you know you're out of job (with no understanding as to why).

With that said anyone who thinks there is privacy in today's world is fooling themselves. Doesn't make this (or other things) right / wrong...just pointing out the reality.

Please, be specific. What are you worried about the police being able to do, could they do that without this technology, and why would they do what you're worried about?

The matter isn't necessarily so much about what can be done with the data right now, which has been determined to be not a whole lot unless your vehicle is already flagged as being of interest, but what can be done once these devices are on every other corner.

It's best that we put realistic limits to how much and for how long they can store the data before it gets to the point where they can monitor the location of every car within the city in near real-time.

Many people have already given concrete examples of how this data could be mis-used by both the public and law enforcement even at the low-level of intrusion already given as well as the frightful manner in which such a system could be so easily abused or even just mis-used through no ill will once it becomes more prevalent.

Ostracus wrote:

How about finding an abducted child?

That wouldn't be part of the "non-hit" data. For things that are flagged, they will mobilize as soon as feasible. For things that aren't flagged, however, the data should be flushed, if not immediately, then within a very short period.

While there are positive uses for keeping the data longer, the possible abuses so drastically outweigh them, that it shouldn't even be a question.